How does exception handling work in Python?

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Python uses `try`/`except`/`else`/`finally`:

- **`try`** wraps the risky code.
- **`except SomeError as e`** handles a specific exception type (and its subclasses). You can have several, most-specific first.
- **`else`** runs only if **no** exception was raised — put the 'happy path' continuation here so it isn't accidentally guarded by the `try`.
- **`finally`** **always** runs (success, exception, or `return`), for cleanup.

Best practices: catch **specific** exceptions, never a bare `except:` (it also swallows `KeyboardInterrupt`/`SystemExit` and hides bugs). Re-raise with a bare `raise` to preserve the traceback, and chain causes with `raise New() from err`. Exceptions are classes in a hierarchy rooted at `BaseException` (most inherit `Exception`), so catching a base type catches its subclasses.

Python's style is **EAFP** ('easier to ask forgiveness than permission') — try the operation and handle the exception, rather than pre-checking with lots of `if`s.

**Interview tip:** exp

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